1. Field of the Invention
The present invention relates to a recording medium player for reproducing a multiplex information-carrying signal which is obtained from a recording medium such as video disc and video magnetic tape and, in particular, to a time axis correction device for correcting or adjusting the time axis of a multiplex information-carrying signal obtained from a recording medium.
2. Description of the Prior Art
It is well known in the art that the time axis correction device is used in a recording medium player such as video disc player and video tape player so as to correct or adjust the time axis of an information-carrying signal obtained from a recording medium thereby to eliminate fluctuations in the time axis of the information-carrying signal due to fluctuations in the relative speed between the pick-up device and the recording medium. In many cases, the information-carrying signal contains a plurality of information-carrying component signals such as a video information-carrying component signal and an audio information-carrying component signal. The respective time axes of the information-carrying component signals are to be adjusted or corrected, respectively, by means of a time axis correction device.
In a prior art time axis correction device, the color burst signal contained in the video information-carrying signal is seperated and compared with a reference signal thereby to produce an error signal which is utilized for correcting or adjusting the time axes both of the video information-carrying signal and the audio information-carrying signal.
It has, however, been a problem that since the color burst signal is absent during the vertical blanking period of the video signal, the time axis correction operation for the audio information-carrying signal is interrupted at every vertical blanking period so that the demodulated audio information signal contains unwanted fluctuations in the time axis thereof. When, for example, the repetition frequency of the vertical blanking periods is 60 Hz, the demodulated audio information signal contains noises of 60 Hz. It is, on the other hand, to be noted that the video information signal is not adversely affected by such interruptions in the time axis correction operation, since no picture is reproduced during such blanking periods.